A fuel cell is an electrochemical energy conversion device that converts energy from the chemical reaction of a fuel and an oxidant into electrical energy. Proton exchange membrane (PEM) fuel cells are the most commonly used for vehicular power plants. In these fuel cells, hydrogen rich gas (H2) is supplied as fuel and oxygen gas (O2) or air is supplied as the oxidant. In the subsequent oxidation-reduction reactions, the H2 is oxidized and reacts with O2 to form water and produce electricity for the operation of an electrical power plant of the vehicle. The stoichiometry of the chemical reactions is such that the amount of water produced is proportional to the power consumed by the vehicle. The operational characteristics of the PEM fuel cell require particular levels of humidity to be efficient. However, in any PEM fuel cell which produces the requisite power to operate a motor vehicle, water is produced far in excess of the amount required to maintain the proper humidity in the fuel cell. Much effort in the design of these cells has been spent in managing the waste water issue.
Due to the economics of motor vehicle energy consumption, much of the design process of motor vehicles has been dictated by reducing vehicle weight and the space of non-passenger areas. This lowers the energy consumption directly by the lowering of weight and indirectly by allowing for more flexibility in the design of aerodynamically important surfaces through minimizing volume requirements imposed on designs. This is particularly important in electrically powered vehicles in which it is more difficult to provide marginal increases in power. Any design changes which allow for reduction in weight or space of electrically powered vehicles would have greater impact on the operational cost when compared to similar changes in gasoline powered vehicles.
Washer fluid systems are necessary for the safe operation of motor vehicles yet place a burden on both weight and space in the present configuration of motor vehicles. The washer fluid mix presently employed in motor vehicles consists primarily of water with antifreeze and cleaning components such as alcohols, amines, and non-ionic detergents. Typically, this mix is stored in premium compartment space to facilitate the operator's ability to refill the storage containers when needed. This results in designs which place large heavy containers, which are primarily filled with water, in premium areas of vehicle space. A design strategy which would call for the storage of only the concentrate form of the washer fluid would radically reduce the space and weight required by the washer fluid system.
What remains needed in the art is to somehow utilize the waste water, produced in the operation of the fuel cell, to provide washer fluid.